NASA’s nuclear-powered Perseverance rover is about to reach at Mars on Thursday with a make-or-break entry, descent, and touchdown. The rover will execute the arrival autonomously, whereas engineers and scientists again on Earth can have a nail-biting 11-minute anticipate alerts to succeed in house confirming the destiny of the $2.7 billion mission.
The one-ton rover is on the ultimate stretch of a seven-month journey from Earth to Mars, in search of to turn into the ninth U.S. spacecraft that has efficiently landed on the Crimson Planet.
The mission is aiming to land inside a 4-mile-wide (7-kilometer) zone inside Jezero Crater, an affect basin scientists imagine was flooded with liquid water billions of years in the past.
Perseverance was ferried to Mars by a cruise stage, which carried photo voltaic panels and thrusters for course correction maneuvers on the 293 million-mile (471 million-kilometer) interplanetary journey. One of many first duties for Perseverance earlier than it might probably land on Mars is to jettison the ring-shaped cruise stage.
Floor groups at NASA’s Jet Propulsion Laboratory in Pasadena, California, anticipate to obtain affirmation of the cruise stage jettison at 3:38 p.m. EST (2038 GMT), though the precise occasion will happen 11 minutes earlier. The cruise stage will deplete throughout entry into the Martian environment, leaving the Perseverance rover — cocooned inside a 14.8-foot-diameter (4.5-meter) thermal defend — to plunge towards the Crimson Planet’s floor by itself.
NASA expects to obtain alerts from Perseverance confirming it has entered the Crimson Planet’s carbon dioxide environment at 3:48 p.m. EST (2048 GMT), kicking off a fast-paced sequence of occasions culminating within the decreasing of the cellular robotic geologist to the Martian floor on its six titanium-supported aluminum wheels. Strain sensors, temperature probes, and cameras will document knowledge throughout Perseverance’s entry, descent, and touchdown.
Engineers at on Earth, some 127 million miles (204 million kilometers) from Mars, anticipate alerts confirming Perseverance’s touchdown at 3:55 p.m. EST (2055 GMT), assuming all the things goes in line with plan.
Right here’s a step-by-step timeline of the entry, descent, and touchdown sequence, starting for the time being Perseverance’s warmth defend first encounters the higher traces of the Martian environment:
- Entry+00:00: Atmospheric entry.
- Entry+01:20: Peak entry heating, with temperatures exterior the warmth defend reaching about 2,370 levels Fahrenheit (1,300 levels Celsius).
- Entry+01:30: Peak deceleration.
- Entry+04:00: Perseverance deploys its 70.5-foot-wide (21.5-meter) supersonic parachute at an altitude of about 7 miles (11 kilometers) and a velocity of about 940 mph (1,512 kilometers per hour). The craft deploys the chute when it detects that it has reached a predetermined distance from the touchdown website.
- Entry+04:20: Perseverance jettisons its no-longer-needed warmth defend, revealing a touchdown radar and cameras to assist the spacecraft navigate to a secure touchdown website.
- Entry+04:50: Radar lock on the Martian floor.
- Entry+05:30: Perseverance obtains a terrain relative navigation resolution through the use of photographs captured by on-board cameras to seek for a secure touchdown website.
- Entry+05:50: The Perseverance rover jettisons its backshell at an altitude of 1.Three miles (2.1 kilometers), releasing the craft’s descent stage to fireside eight throttleable retrorockets to sluggish for touchdown. After reaching an altitude of about 66 ft, or 20 meters, the descent stage will decrease the rover on Nylon cords to a distance of about 25 ft (7.6 meters). The rover’s wheels will deploy earlier than setting down in Jezero Crater.
- Entry+6:50: Perseverance lands on Mars. Pyrotechnics will hearth blades to sever the Nylon cords connecting the rover to its descent stage, which can propel itself a secure distance away earlier than impacting the Martian floor.
Engineers and scientists at JPL will pay attention for alerts from Perseverance all through the entry, descent, and touchdown. The rover is programmed to beam again standing tones through a direct-to-Earth antenna at every milestone.
“We will use these tones to inform us various things like the warmth defend has come off, or one thing like that,” mentioned Allen Chen, the Perseverance rover’s entry, descent, and touchdown lead at JPL. “Sadly, as soon as we get all the way down to backshell separation, Earth will set under the horizon for Perseverance, so the tones will finish.”
NASA’s Mars Reconnaissance Orbiter can be flying over Jezero Crater when Perseverance lands. The long-lived orbiter, about to mark 15 years at Mars, will relay a trickle of knowledge from Perseverance again to Earth in near-real time
“That offers us about about eight kilobits per second of knowledge,” Chen mentioned. That’s type of like half the velocity of old-fashioned dial-up in case you, in case you
keep in mind that. However that will enable us to see quite a lot of various things, like what the car is doing … We’ll be capable to see what mode we’re in, the place we predict Perseverance is trying, how briskly we’re going, and the way excessive we’re above the bottom, even the estimate of how a lot gas now we have left as nicely.”
NASA’s MAVEN orbiter can even be in vary of Perseverance throughout touchdown, however MAVEN gained’t ship the information it data till a number of hours later.
However not one of the telemetry streams are required for Perseverance to land on Mars. “Perseverance will attempt to land herself, it doesn’t matter what, even when we don’t get any of that knowledge,” Chen mentioned.
If all goes in line with plan, Perseverance may ship house its first “thumbnail” photographs from its hazard cameras moments after touchdown by way of the MRO radio relay, revealing the view of Jezero Crater for the primary time.
“As soon as we do get down safely on the floor, we’re all on the sting of our seats to get these first photographs from Mars,” mentioned Jennifer Trosper, the rover’s deputy challenge supervisor at JPL.
NASA’s Odyssey orbiter will fly over Perseverance’s touchdown website about three-and-a-half hours after landing. Odyssey will relay knowledge on the standing of the rover, however it’s unlikely floor controllers will get contemporary photographs throughout Odyssey’s move, in line with Trosper.
At round 9:30 p.m. EST Thursday (0230 GMT Friday), the European ExoMars Hint Gasoline Orbiter will fly over Jezero Crater. The European orbiter can be positioned to relay a considerably larger quantity of knowledge from the rover.
“Hopefully, we’ll be getting some preliminary photographs,” Trosper mentioned. “These could be the entrance and rear hazcams with the lens covers deployed, as a result of the rover should deployed them by then.”
The ExoMars orbiter may present low-resolution previews of images taken by Perseverance’s touchdown cameras throughout descent, Trosper mentioned.
Trosper mentioned the Perseverance rover will unfurl its high-gain communications antenna and launch digicam lens covers shortly after touchdown, earlier than going to sleep to recharge batteries for added activations within the coming days and weeks.
One essential process can be to find out the orientation and slope of the rover on Mars. That info will assist floor groups inform Perseverance the place to level its high-bandwidth communications antenna to attach with NASA’s Deep Area Community on Earth.
Perseverance can even elevate its distant sensing mast, fitted with a panoramic zoom-capable digicam, science instrumentation, and a Martian climate station. Then floor crews will command Perseverance to take its first brief take a look at drive, setting the stage for a mission deliberate to final not less than two years searching for indicators of historic Martian life, and accumulating rock samples for return to Earth by future spacecraft.
Perseverance can even launch NASA’s Ingenuity helicopter a while within the subsequent few months. The JPL-built rotorcraft would be the first such car to fly by way of the environment of one other planet, and groups plan a number of low-altitude, short-duration take a look at flights earlier than Perseverance continues on with its major mission.
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